I can't watch any of the videos or anything right now, but Im gonna say the TDI. The A6 in general is a whole lotta car, and a V6TT TDI is nothing to scoff at. After that it might just be excessive, for a luxury sedan like this. Also if I were badge-conscious, buying the TDI isn't a badge to be ashamed of IMO.

Originally Posted by UNBANNED_GERBIL

Phew!!! Thank goodness it's a VW troll thread. If it were a Hyundai troll thread the bukkake faced fanboys would be frothing at the mouth

Neither choice is lacking in that. The gas engine may have less overall torque, but the powerband is way way wider. The torque peak is longer than the whole powerband of the diesel (more powerful S8 engine shown).

I voted the diesel because the Hp/Tq are both already so great that for everyday use, the difference would be negligible. Both cars are very quick and the ability to hit 40mpg would blow me away. It is one thing to line up next to a car and blow them away with hp & speed but to do both while besting their mileage greatly at the same time is a very powerful statement.

It'd be hugely rapid and likely deliver high 20's on the city cycle. In a car like the A6, that's fantastic--and much better to live with in the real world than the S6, which would likely return 16-18 I'd think (for comparison, I barely get more than 22mpg in my GTI on my daily commute, which averages 18-19mph).

However, the S6 is huge value against cars like the Merc and M5. Honestly, I couldn't see myself stretching to buy an M5 over the S6.